After more than 20 years, NASA today said goodbye to the Cassini space probe and sent it plunging into Saturn's atmosphere to burn up. It was the end of a remarkable mission that revealed deep secrets of the ringed planet and its many moons.

Florida utility representatives say parts of the state will require a "wholesale rebuild of our electrical grid" after Hurricane Irma left millions without power. How can Florida and other states build electrical grids that are resilient to natural and other disasters?

We humans have been dropping "um," "uh" and other expressions of hesitation into our speech for a long time — maybe for as long as we've had language. More recently, linguists are noting a shift in usage across a number of Germanic languages from "uh" to "um."

Scientists are warning West African villagers to stop hunting bush meat and to stay away from fruit bats as they circle in a possible animal source for the latest Ebola outbreak. The Ebola virus lives in fruit bats, scientists believe, and is threatening communities who are already facing the deadliest Ebola outbreak in history.

Genetically modified crops are a big part of both our food supply and our debates about health and safety. But some scientists and observers argue those debates are getting the science of GMOs wrong, and grouping together crops that don't belong in the same argument.

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05/04/2015 - 3:45pm

The scientific consensus around Alzheimer's disease says it's caused by proteins called beta-amyloids that build up on the brain and destroy its normal functions. But one man, Duke professor Allen Roses, has made it his mission to prove that the conventional wisdom is wrong.